Refrigerator



l REFRIGERATOR original Filed May 2, 1932A 2 sheets-sheebl W. HIRCHE REFaIGEn-oa- March 2l, `1939.

Origial Filed May- 2, 1932 2 Sheets-Sheet 2 Reissued Mar. 21, 1939 f".^'1hlslnvention' 'relates to a refrigerator of the'ftypeiin"whivihf'asv refrigerating `medium a liquidil is `employedfwl'iichl' does not combine with the lubricant butfseparates therefrom. The invention' Lrelates chiefly to "a "refrigeratingliquid which is heavier than lubricating voil so that the connected withv-refrigerators in which pure 'oil is employed for the 'lubrication of the elements of compressor mechanism'consists in that the oil which has to come into touch with the mechanism or lthe oil which-has been carried off by Ihe refrigerating vapors cannot return into the (il collecting compartment Iproper without spe-` |5 cial auxiliary means', so that the circulation of the oil is not continuous. Several collecting noints for the oil'are formed vin they refrigerator,

)rom which points ther oil must be returned by pumps or other suitableauxiliary means tothe 0 oil collecting point proper. f Apart from'the fact that such a` method is complicated, there is no guarantee for a regular and uniform lubrication. Such refrigerators require careful obser vation which is not compatible with;` thev pecu- 5 liarity of their purpose of use.' Refrigerators must not be delicate and must require little attention; Once such a machine has been taken into service, it must continue to workl for a long period Without observati'on, this being only possible lf the lubricating oil is automatically, uni- .plant and has no opportunity of collectingl in leoting chamber proper. y.

'The refrigerator according to the vinvention is of such aV machinentype which comprises only maincollectingl point after'V it'has fulfilled its eating oil which is fed to the'gearing elements is adapted to the requirements.

It is thus an object of the 'invention' to provide a refrigerator in which 'a refrigerantmedium and -a lubricantl are employed which medium andV lubricantfdo not mix 'with each other and-the refrigerant in' its liquid state is'heavier thereon, in which 'a container is provided containing refrigerant in-the liquid state and lubricant iioating on the surface of said refrigerant liquid together with means for transferring the lubricant to the mechanism of the refrigerator requiring lubrication and for returning'the lubricant from said niechanismto said container.

.L I jaamoaaaroa .-...Willy'Hh-che, Deopoldshain, near Gorlitl, r- 1. qmany, assignor, bywmesne assignments, to'E. A R.otlh enberg, Berlin, Germanyv x l original No. 2,o1s`,s31,jdad october s, 1935.y se rial No. 608,750, May 2; 1932. Appllcationlor 4 reissue'October'l, 1937, Serial No. 166,859, lIn Germany January 2,11930 f is claims.- (or {sz-1,15)

' oil consequently floats on it. An inconvenience formly. and continuously circulated through the large quantities anywhere except in the Aoil -copl`v one main oil collectingcompartment, the, lubr`i' cating oil returning always automatically to the duty. carre is' taken that the quantity 'of i'ubrif than the lubricant which may therefore oat` .through the alter tube s.

several embodiments vof thelnventlon' are 11- lustrated by way of 'example in the accompanying drawings `in which;

Fig. 1 shows diagrammatically-a'form of constructioniin section. 5

Fig. 2 is asimilar view of a modmedform of Fig. 3"is 'a longitudinal section of Ia. third form of construction. y n

Fig. 4 isa` section on line IVf-IV of Fig. 3. 1n

In all vthe formsof construction shown on the y drawings a compressorI cylinder 2 and a casing 3' of the driving motorare gas-tightly connected to a crank case I. A crankshaft ,lis journaled at 5 and 6in the crank case I and directly cou- 15 pled to the rotor 1 of the'drivlng1 motor. 'I'he shaft 4 is not journaled in the motor casing 3 but carries the motor on its overhanging end. The result is that the oil or other lubricant is prevented from entering` they casing 3 which is 2G tightly closed for this purpose by a packing Il. The casing 3 can be removed from the crank case I in order to render the'motor accessible for repairs or exchanging'.y When the casing 3 is removed, the`crank case I is not open, to the atmosphere, being still closed by thepacking B. y The limerI spacev of the casing 3 is connected to the innervv space of the crank fcase I by a tube 9 but this tube is lled with a fine granular substance and actingjlik'e a ilter, so that, even when 30 the casing 3 is removed, only very 'small quantities of gases or liquid can escape. The object of the tube il is, to establish' a connection between the motor casing 3 and the crank case I which is only slightly .permeable to gas but al- 35.

moisture from 'the motor'casing which .would 40 l have a destructive effect on the motor winding. In the case of suction eectwbeing exerted for a sufficiently long period, all air and moisture will be removed from themotor casing. It is advisable, when thev plant is working,`to supply refrig'erating medium gas to the air in the interior of the casing I considerably rareed by exhaustion in order to produce a medium which conducts to the casing the Vheat developing in the motor winding. This feeding of the refrigerating medium gases into the casing l is effected If. in spite of all packing means, oilshould deposit in the motor casing, it-can trickle back into the crank case I through the tube 0. The oil passing with the ing mixes with the ilne metal particles which have become detachedfrom the parts of the motor subjected to friction and thus forms a' good conductor for the electric current. The polluted oil soon penetrates to thewinding of f the motor and the metal particl cause a shortin`g between the windings of the stator winding. Ii it is desired to prevent this by multiple insulatig of the winding. very cumbersome dimensions of the -stator result and the danger still exists that at sharp transition points the insulation will become so damaged by mechanical actions that it no longer works. perfectly. A covering of the heads of the winding of the stator with a sheet metal hood certainly protects the winding against. the penetration of oil but ,it prevents evacuating of the air and moisture from the enclosedv space, this evacuating being however absolutely necessary in order to protect the insulation and the winding against destruction and to thusv prevent any shorting in 4the wnding. According 'tothe invention thev heads I3 of the winding of the stator are covered with a hood II of lter cloth or some other suitable fabric which prevents the metal particles mixed with the oil from penetrating to the insulation of the winding, but allows the evacuagon of air from the winding enclosed by the ood.

'I'he lower portion oi' the crank case i merges into an evaporator I2 or is detachably connected thereto. Cooling ribs I3 project in outward direction from the evaporator. At the point of transition between the crank case I and the evaporator I 2 a hood I4 is arranged which separates the two compartments and has at its centre a rising pipe Il. The evaporator contains the refrigerating medium liquid, for example sulphur dioxide. An oil collector Il is pro-v vided at the lower portion of the crank case I. The gases forming in the evaporator pass through `the hood Il and the pipe I5 above the oil level -in the crank case. lIhe speed of travel of the gases increases in the pipe I5 so that small quantitles of oil are sucked in by the gases out of the oil compartmentV through small holes I1 in the wall of the pipe I5 and fed to the operating mechanism parts. The oil dripping from these parts drops back directly into the oil collectingcompartment. Any refrigerating medium which condenses in the crank case collects in the lower part of the crank case I as it is heavier than oil and passes through a small aperture Il at the base of the hood back into the evaporator. The gases passing through the pipe Il into the crank case are forced into a condenser 2l by a piston 2l connected by a piston rod I9 to the crank shaft l. The gases condense in the condenser Il and return in liquid state through a conduit 22 into the evaporator. 'I'he oil particl carried into the condenser return along the same path into the evaporator, where they. iioat on the surface of the liquid refrigerating medium and,

when the level oi' the liquid has sumciently risen, pass throughthe hole I3 into the oil collecting compartment.

In the form of construction shown in Fig. 2 the crank case I merges directly into the evap` orator so that no partition exists between the two. The yoil also oats on the liquid refrigerating medium in the evaporator and the level of the oil is so high,.that the crank 33 when in .t0 brins the vmost the entire length lof the evaporator.

-passage of the oil.

'refrigerating medium vapors into the motor casflung about in the casing bythe crank thus reachesallmechanismparts. Insteadofaliowing the crankvto dip into the oil, it is possible level close to the crank in its lowermost tion and to arrange lubricating chains, rings or the like on the crank shaft which dip into the oil andfeed it to the mechanism parts. Other feeding means may however be provided to bring the oil into contact with the gear parts. Thevoil dripping oi! drops directly into the oil collecting compartment. The ascending gases pass through the oil layer. take up oilparticles and conveythem to the mechanism parts. The refrigerating medium, condensing in the crank case, being heavier than oil, sinks through the oil layer andiiows back into the evaporator. Y

In the form of construction illustrated in Figs.

3' and 4 a boiler-like evaporator 2l is connected to the crank case and tubes 28 extend through this evaporator 2|. The evaporator 24 has a dome-like superstructure 21- which extends al- 'I'he evaporator wall is open along the length and width of the dome 21 so that the gases rising in the evaporator can ilow along the shortest path and collect in the upper portion of the dome. In order-to facilitate the rising of the gases, the tubes are preferably so arranged that their distance apart in the horizontal direction continualvly increases in the superposed rows. 'I'he upper portion of the evaporator 24 and the lower portion of thedome 21- form an oil collecting compartment 2l. Between the crank case I and the evaporator 24 a partition 28 extends so that the gases are conducted through a pipe 3 0 into the crank case, the other end of the pipe 30 being located in the gas space of the dome. The pipe 3l is of U-shape and its middle portion extends below the oil layer through the evaporator. To

the lowest point of this suction pipe 3l a tube 3| of a filter 32 is connected like a nozzle. 'the pipe 3l being widened at the point of connection 33. The illter is filled with a fine granular substance 34 which allows the oil to pass through only in drops and has in its upper portion, ex-

tending into the stored oil, holesl 35 for the The filter is surrounded by a casing 36 forming an annular space with the ilter 32 which space is also filled with a suitable filtering substance Lateral holes 31 in the upper portion of the casing 3l allow oil to pass therein.

By choosing a suitable substance for vfilling the lter the quantity oi' oil passing therethrough can be adapted to the quantity of oil required. I'he oil drips through the tube 3| into the suction pipe 3l at it's widened portion 33. Owing to the widened cross sectionI of the pipe 30 the speed of the gas sucked by the compressor is reduced' to such an extent at this point that the gas can not exert any suction eil'ect on the oil. Consequently, the oil drips freely and isonly carried on by the gases when itvarrives in the narrower portionof the suction pipe. Thus, the gas can never carry off more oil 'than drips from the filter. If necessary, the quantity of oil flowing through the illter can be regulated. It is evident, that some other suitable throttling elements may be fitted instead of the filter illustrated. Theloil drilling fromfxhe mechanism parts collects in thelower portion of the crank case and passes -into a pipe 3l extending through the bottom of the crank case and terminating above the partition 29.' This pipe 38 is constructed like a amas 'thus suddenly'nemptied. This emptying always takes place automaticallyat intervals dependent upon the 'quantity vof oil collecting inlthe crank case.l Consequently, the oil levelin the evaporator isv regulated automatically and is thus maintained l:sita constantheight. Instead ofthe lsiphon pipea straight' pipe mightbe employed.

the upper end of which terminates above the partition 29 in the crank case and the lower end of which terminates inthe oil space of the evaporator. `'li'heeii'ect however would. then not be as perfect, as that of the siphon pipe. The oil in this case would only flow in the pipe by gravity, the' flowing taking place only when so much oil has collected above the pipe that thepres'sure on the oil column is greater than the counterpressure caused by the'pres'sure inthe evaporator and by-the vacuum in the crank case. Y

In the construction illustrated in Figs. 3 and 4 the evaporator need not be connected directly to the crank case, as the same effect would take place if the two parts are spatially separated and interconnected by the pipes Stand 38. 'I'he construction according to Figs, 3 and 4 is not restricted to the employment of a liquid refrigeratingV medium which is heavier than lubricating oil, it operates equally advantageously if the liquid refrigerating medium oats on the lubricating oil, only the filter 32 must be arranged in the oil compartment. l

'Ihe especially large oil space in conjunction with the regulated quantity'of lubricating oil fed to the mechanism parts and the automatic returning of the. lubricating oil Vto the collecting chamber ensure a permanently reliable circulation of the oil and a constant oil level..

It will be noted vthat the constructions shown and described will serve admirably to accomplish the objects stated above. It is to be understood. however, that the constructions disclosed above are intended merely as illustrative of the invention and not 'as limiting as various modifications therein may be made without de# parting from the invention as dened by a proper interpretation of the claims which follow.

I claim;

1. A refrigerator inv which as refrigerating medium a liquid is employed which does not combine with the lubricating oil, comprising in combination a crank case, an oil collecting chamber below and communicating with said crank case, an evaporator under said crank case andsep-v arated from said crank case by said oil vchamber, a compressor connected to said crank case, and a pipe extending through' said oil chamber having small feed apertures adapted to accelerate the passage speed of the gases sucked from said evaporator by 'said compressor to cause the gases to draw oil through the holes in said pipe and convey the same into said crank case.

2. A refrigerator in which as refrigerating medium a liquid is employed which does not 'combine with lubricating oil, comprising in combination a crank case, an evaporator on the lower end of and communicating with said crank case. a condenser on the upper end of said 'crank case, and an ejection conduit adapted to convey the condensed refrigerating medium from said condenser to said evaporator and terminating in said evaporator approximately at the line of .transition between 4the. refrigerating medium and theloli floating thereon.

3L vA' refrigerator'inwhich as refrigerating medium a iiq'uidfisA employed which does not combine with lub y tion a crank casejan oil collecting chamber. below and .communicating with said crank case, an

evaporator underv said chamber.` afhood on said evaporatorl separating the same from said .box and having an aperture near its lower edge for the return otfcondensed refrigerating medium fromsaidfcr'ank icase to said evaporator, and a pipe rising from said hood forming withsaid hood `and the lower .portion oi said crank case an oil collecting chamber. f l

4. A refrigerator .in which as refrigerating medium a liquid is employed which vdoestnot combine' with lubricating oil, comprising in combination a crank case, a crank shaft .journalled in and projecting from said crank case,an overhanging rotor mounted on the free end of said crank shaft, a stator surrounding said rotor, a casing enclosing said rotorand carrying said stator detachably connected to said crank casey adapted to give access to said, rotor and said stator. and a packing between said crank case and said casing adapted to prevent oil from passing from said crank case into saidv casing.

5. A refrigerator in whichy as refrigerating medium a liquid is employed which'does not combine with lubricating oil, comprising in combination a crank case, a motor casing on said crank case, m'eans for preventing the penetration of oil .but allowing a limited penetration of refrigerating medium gases'from said-crank case into said motor casing. f

' 6. A refrigerator in which as refrigerating medium a liquid is employed which does not combine with lubricating oil, comprising in combination a crank case, an evaporator under said crank case, a motor casing on said crank-case, apacking between said crank case and said motor casing adapted to prevent oil from passing, but to allow the restricted passage of gases from said crank case to said motor casing, and a filter likeconnection` between said motor casing and said kevaporator adapted to allow a throttled passage of refrigerating medium gases ,to pass to said motor casing and in conjunction with said packing to allow a circulation of gases through said motor casing.

. 7. A refrigerator in whichas refrigerating medium a liquid is employed which does not combine with lubricating oil, comprising in combination a crank case, a motor casing on said crank case, and adjustable means between lsain crank case and said motor casing adapted to -regulate the passage of gas through said motor tingoil, comprising inv combinadium a liquid is employed which does not comi bine with lubricating oil, comprisingl in combinavtion a crank case, a motor casing on said crank `dium a liquid is employed which. does not combine with lubricating oil, comprising in combination a crank case, a crank shaft journalled in said crank case on said evaporator extending from said crank case forming at the same time 40 connected tol said filter tube adapted to reduce the ou collecting cnambergthe level or the pure lubricating oil floating on but not mixed with the liquid refrigerating medium in said evaporator extending up to the crank of said crank shaft .which crank dips vinto and distributes the oil to said crank parts. Y

10. A refrigerator in which as refrigerating medium a liquid is employed which does notcombine with lubricating oil, comprisingin combination a crank case,ian oil chamber below and communicating with said crank case, an evaporator below saidoil chamber, a suction pipe between said crank case and said evaporator extion a crank case, an oil chamber below and communicating with said crank case, an evaporator under said oil chamber, a suction pipe in said evaporator extending to above the level of oil in said Voil chamber. and a filter in said oil chamber having lateral perforations at its upper end and communicating at its lower end with the interior of said pipe.

12. AE refrigerator in which as refrigerating medium a liquid is employed which does not combine with lubricating oil. comprising in combination a crank case, an oil chamber belowand communicating with said crank chamber, an evaporator below said oil chamber, a suction pipe in said evaporator extending to above the level `of oil in said oil chamber, a nlter in said oil chamber, and a widened portion of said pipe the ow of gases from said evaporator at the point ofconnection with said filter tube to prevent suctionl effect being exerted on `said lter tube.

13. A refrigerator in which as refligeratlng medium a liquid is employed which does not combine with lubricating oil, comprising in combination with the crank case. an oil chamber below and communicating with said crank case, an evaporator containing said oil chamber, and a pipe connection between said crank case and said evaporator to conduct the oil collectedin said crank case to said oil chamber, the upper end.of said pipe terminating in said crank case and its lower end in said oil chamber.

14. A refrigeratorl inV which as refrigerating medium a liquid is employed which does not vcombine with lubricating oil, comprising in combination with the crank case, an oil Achamber below and communicating with said crank case, a siphon-like pipe between said crank case and v'said oilcbamber adapted to exert a siphon-like effect on the oil collected in said crank case and to return this collected oil into said chamber.

l5. A refrigerator in which as refrigerating medium` a liquid is employed which does not combine with lubricating oil, comprising in com-- bination an oil chamber. an evaporator below said oil chamber o boiler-like construction communicating with said oil chamber byperforations in its upper wall distributed over the entire length andwidth of said oil chamber, said oil chamber being made like a boiler dome'and having a space for collecting the gases rising from said evaporator.

16. A refrigerator in which as refrigerating I medium a liquid is employed which does not combine with lubricating oil, comprising in combination an oil-chamber, an evaporator under said oil chamber of boiler like construction and tubes in said oil chamber for the circulation of the refrigerating medium arranged horizontally in several rows the spacing of the tubes in the different rows widening successively in each superposed row to facilitate the rising of the gas bubbles in said evaporator.

l'l. A refrigerator in which a refrigerating medium and a lubricant are employed, which refrigerant and lubricant do not mix with each other and the refrigerant in its liquid state is heavier than the lubricant, comprising compressor mechanism including an operating element cate the compressor mechanism and a e for returning lubricantv from said mechanism to said evaporator, the construction and arrangement being such that the said operating element of said compressor mechanism periodically dips into the lubricant stored in said evaporator.

18. A refrigerator in whichk a refrigerating medium and a lubricant are employed, which refrigerant and lubricant do not mix with each other and the refrigerant in its liquid state is i heavier than the lubricant, comprising' in combination with a compressor including .a crank case within which means for operating the compressor is housed, an evaporator. located immediately below the compressor operating mechanism and forming a continuation of the crank case, the upper portion of said evaporator formc 

